Atrial flutter is a supraventricular arrhythmia in which the atria contract at a rate of 250-350 bpm. The ventricular response depends on the degree of block at the atrioventricular node.
Often the atria contract with a rate of almost exactly 300 bpm and commonly there is a 2:1 block. Hence one should always consider atrial flutter in a narrow complex tachycardia with a rate of 150 bpm
Note that, in the context of long term management of atrial flutter, NICE state the management is as for atrial fibrillation:
Last edited 08/2020 and last reviewed 08/2020